Democrat
The violations included unsafe handling and storage of explosive and flammable chemicals, missing labels on storage tanks, failing to pressure-test hoses, bad or missing valves, and failing to have an emergency response plan. The agency also said that some workers were not trained for their jobs.

OSHA, which also proposed a fine of $118,300, decided to issue the citations now, during the government shutdown, to avoid a statute of limitations problem, Ms. Boxer said. She said that while the fine was disproportionately small, considering the deaths, injuries and widespread damage, other federal agencies were also investigating the explosion. Some of those investigations have been delayed by the shutdown, however.

Ms. Boxer is chairwoman of the Senate’s Environment and Public Works Committee, which does not oversee OSHA but does oversee another agency with jurisdiction at the Texas plant, the Environmental Protection Agency.

Ms. Boxer said that despite the shutdown, news of the enforcement action should be disseminated to...